SEARCH Articles Figures Tables 1- naphthalene sulfonic acid, 3-Hydroxy- 4- -7-nitro 1-naphthalene sulfonic acid, 7-Hydroxy-, sodium 2-Hydroxy-1- naphthalene-4-sulfonic acid 2-Hydroxy-2-propane sulfonic acid 2-naphthalene sulfonic acid, 8-Hydroxy-5,7 dinitro 4- Hydroxy-3- azobenzene-4’sulfonic acid 6-amino-4-hydroxy-2-naphthalene-sulfonic acid 8-Hydroxy-5-quinoline sulfonic acid 8-Hydroxy-7-aminoquinoline-5-sulfonic acid 8-Hydroxy-7-iodoquinoline-5-sulfonic acid Hydroxy sulfonic acids formation L-Hydroxy-2- naphthalene-4-sulfonic acid Sulfones, hydroxy